Rupert Grint could feel Alan Rickman looming behind him as he drew an unflattering portrait of Rickman's character Severus Snape while filming a potions class.
"I was absolutely terrified," laughed Grint, who played Ron Weasley in all eight of the Harry Potter films. "He was a great actor. … I'm sad to see him go."
Grint told a throng of reporters at Universal Studios Orlando's third annual A Celebration of Harry Potter on Friday night that news of Rickman's death was "quite a sideswipe. I was devastated last week."
This weekend, he'll be celebrating the 10 years of his life that he spent filming the beloved children's book series authored by J.K. Rowling. Cast mates Evanna Lynch (Luna Lovegood), Matthew Lewis (Neville Longbottom), Katie Leung (Cho Chang) and Bonnie Wright (Ginny Weasley) are also participating in this year's three-day event, which ends Sunday. The cast will be holding a panel discussion for fans on Saturday and Sunday at the theme park.
Despite grappling with the loss of Rickman's, the cast also shared happy memories of their time at Hogwarts.
"I nicked a spoon," said Leung, who is joining the celebration for the first time. "I don't know why. It was at the ball (in the fourth film) when we had all the fancy cutlery and I just took it."
Warner Bros. Pictures, the studio that produced the films, kept the props under tight wraps — even requiring every person to check in their wands every day, Wright said.
"If I had stolen anything, I couldn't have told you unless I wanted Warner Bros. after me," she said with a laugh.
Grint knows exactly what she means. He stole the golden egg from Harry Potter and the Goblet of Fire only to be tracked down after 13 hours by studio staff.
"Apparently, it was worth $10,000," he said.
He did get to keep one souvenir. Grint took the house number for No. 4 Privet Drive.
The cast will be sharing interesting tales from the set and life after Potter all weekend for the celebration, which draws thousands from around the world every January.
What won't they talk about? Details of the upcoming Fantastic Beasts and Where to Find Them starring Eddie Redmayne or Rowling's new stage play premiering this summer in London: Harry Potter and the Cursed Child.
"I was just on a set visit a couple of weeks ago and I don't know what's known or what I can say, so I won't say anything," Lewis said. "But I'm really excited for what they are about to share with you all. It's absolutely amazing."
Wright, Leung and Lewis all felt that 10 years was enough time playing one character, and didn't feel sad about not being a part of the next chapter in the Harry Potter saga.
Grint felt otherwise.
"They made a terrible mistake in not casting me," he joked.